I like Ubuntu and I don't use Windows except at office but I have always felt that every thing in Ubuntu/Gnome is a bit bigger than it should be i.e the fonts, desktop icons, the window borders and every thing else. This thing really annoys me when I am working in Eclipse. As a developer, desktop real estate is really important for me and I cant afford to waste it.

So the question is how can I make things look more like Windows i.e crispier and smaller?

I have attached the screen shot of same version of Eclipse running on Windows and Ubuntu at same resolution (1400*900)

UPDATE:
I am actually using Ubuntu 10.10 but at the time when I wrote this question I only had 9.10 machine available to me so I used it to get screen shot.

I want things to be compact, not exactly windows like. I say windows because it looks lot more space efficient and I don't like the wasted space. Also I know that I can tweak almost every aspect of GNOME seperately but I want something that can do this for me like some theme or some thing else that can later be easily undone (if I dont like it)

For font sizes and smoothing options, check the Appearance Preferences > Fonts tab. Then click on the "Details" button:

Play with the settings till you get what you like.

If I understand correctly, you're not really after the Windows theme. So you can keep the default gnome look, or - which most would probably prefer - try out different themes (and there are quite a few that are really good). Check out http://gnome-look.org/ and http://www.deviantart.com/. Both sites have some really good themes and other customization tools to make gnome look very different than the default.

To get a little more vertical space you can also try to put any menus, indicators, selectors, etc. on a single panel. I changed to using a single vertical panel just to generate space on my widescreen monitor. Vertical space is at a premium, horizontal space is abundant.